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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/acpi/resources/rscalc.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/acpi/resources/rscalc.c')
-rw-r--r--drivers/acpi/resources/rscalc.c841
1 files changed, 841 insertions, 0 deletions
diff --git a/drivers/acpi/resources/rscalc.c b/drivers/acpi/resources/rscalc.c
new file mode 100644
index 00000000000..8a5f0a52371
--- /dev/null
+++ b/drivers/acpi/resources/rscalc.c
@@ -0,0 +1,841 @@
+/*******************************************************************************
+ *
+ * Module Name: rscalc - Calculate stream and list lengths
+ *
+ ******************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2005, R. Byron Moore
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions, and the following disclaimer,
+ * without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ * substantially similar to the "NO WARRANTY" disclaimer below
+ * ("Disclaimer") and any redistribution must be conditioned upon
+ * including a substantially similar Disclaimer requirement for further
+ * binary redistribution.
+ * 3. Neither the names of the above-listed copyright holders nor the names
+ * of any contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGES.
+ */
+
+
+#include <acpi/acpi.h>
+#include <acpi/acresrc.h>
+#include <acpi/amlcode.h>
+#include <acpi/acnamesp.h>
+
+#define _COMPONENT ACPI_RESOURCES
+ ACPI_MODULE_NAME ("rscalc")
+
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_rs_get_byte_stream_length
+ *
+ * PARAMETERS: linked_list - Pointer to the resource linked list
+ * size_needed - u32 pointer of the size buffer needed
+ * to properly return the parsed data
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Takes the resource byte stream and parses it once, calculating
+ * the size buffer needed to hold the linked list that conveys
+ * the resource data.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_rs_get_byte_stream_length (
+ struct acpi_resource *linked_list,
+ acpi_size *size_needed)
+{
+ acpi_size byte_stream_size_needed = 0;
+ acpi_size segment_size;
+ u8 done = FALSE;
+
+
+ ACPI_FUNCTION_TRACE ("rs_get_byte_stream_length");
+
+
+ while (!done) {
+ /*
+ * Init the variable that will hold the size to add to the total.
+ */
+ segment_size = 0;
+
+ switch (linked_list->id) {
+ case ACPI_RSTYPE_IRQ:
+ /*
+ * IRQ Resource
+ * For an IRQ Resource, Byte 3, although optional, will always be
+ * created - it holds IRQ information.
+ */
+ segment_size = 4;
+ break;
+
+ case ACPI_RSTYPE_DMA:
+ /*
+ * DMA Resource
+ * For this resource the size is static
+ */
+ segment_size = 3;
+ break;
+
+ case ACPI_RSTYPE_START_DPF:
+ /*
+ * Start Dependent Functions Resource
+ * For a start_dependent_functions Resource, Byte 1, although
+ * optional, will always be created.
+ */
+ segment_size = 2;
+ break;
+
+ case ACPI_RSTYPE_END_DPF:
+ /*
+ * End Dependent Functions Resource
+ * For this resource the size is static
+ */
+ segment_size = 1;
+ break;
+
+ case ACPI_RSTYPE_IO:
+ /*
+ * IO Port Resource
+ * For this resource the size is static
+ */
+ segment_size = 8;
+ break;
+
+ case ACPI_RSTYPE_FIXED_IO:
+ /*
+ * Fixed IO Port Resource
+ * For this resource the size is static
+ */
+ segment_size = 4;
+ break;
+
+ case ACPI_RSTYPE_VENDOR:
+ /*
+ * Vendor Defined Resource
+ * For a Vendor Specific resource, if the Length is between 1 and 7
+ * it will be created as a Small Resource data type, otherwise it
+ * is a Large Resource data type.
+ */
+ if (linked_list->data.vendor_specific.length > 7) {
+ segment_size = 3;
+ }
+ else {
+ segment_size = 1;
+ }
+ segment_size += linked_list->data.vendor_specific.length;
+ break;
+
+ case ACPI_RSTYPE_END_TAG:
+ /*
+ * End Tag
+ * For this resource the size is static
+ */
+ segment_size = 2;
+ done = TRUE;
+ break;
+
+ case ACPI_RSTYPE_MEM24:
+ /*
+ * 24-Bit Memory Resource
+ * For this resource the size is static
+ */
+ segment_size = 12;
+ break;
+
+ case ACPI_RSTYPE_MEM32:
+ /*
+ * 32-Bit Memory Range Resource
+ * For this resource the size is static
+ */
+ segment_size = 20;
+ break;
+
+ case ACPI_RSTYPE_FIXED_MEM32:
+ /*
+ * 32-Bit Fixed Memory Resource
+ * For this resource the size is static
+ */
+ segment_size = 12;
+ break;
+
+ case ACPI_RSTYPE_ADDRESS16:
+ /*
+ * 16-Bit Address Resource
+ * The base size of this byte stream is 16. If a Resource Source
+ * string is not NULL, add 1 for the Index + the length of the null
+ * terminated string Resource Source + 1 for the null.
+ */
+ segment_size = 16;
+
+ if (linked_list->data.address16.resource_source.string_ptr) {
+ segment_size += linked_list->data.address16.resource_source.string_length;
+ segment_size++;
+ }
+ break;
+
+ case ACPI_RSTYPE_ADDRESS32:
+ /*
+ * 32-Bit Address Resource
+ * The base size of this byte stream is 26. If a Resource
+ * Source string is not NULL, add 1 for the Index + the
+ * length of the null terminated string Resource Source +
+ * 1 for the null.
+ */
+ segment_size = 26;
+
+ if (linked_list->data.address32.resource_source.string_ptr) {
+ segment_size += linked_list->data.address32.resource_source.string_length;
+ segment_size++;
+ }
+ break;
+
+ case ACPI_RSTYPE_ADDRESS64:
+ /*
+ * 64-Bit Address Resource
+ * The base size of this byte stream is 46. If a resource_source
+ * string is not NULL, add 1 for the Index + the length of the null
+ * terminated string Resource Source + 1 for the null.
+ */
+ segment_size = 46;
+
+ if (linked_list->data.address64.resource_source.string_ptr) {
+ segment_size += linked_list->data.address64.resource_source.string_length;
+ segment_size++;
+ }
+ break;
+
+ case ACPI_RSTYPE_EXT_IRQ:
+ /*
+ * Extended IRQ Resource
+ * The base size of this byte stream is 9. This is for an Interrupt
+ * table length of 1. For each additional interrupt, add 4.
+ * If a Resource Source string is not NULL, add 1 for the
+ * Index + the length of the null terminated string
+ * Resource Source + 1 for the null.
+ */
+ segment_size = 9 +
+ (((acpi_size) linked_list->data.extended_irq.number_of_interrupts - 1) * 4);
+
+ if (linked_list->data.extended_irq.resource_source.string_ptr) {
+ segment_size += linked_list->data.extended_irq.resource_source.string_length;
+ segment_size++;
+ }
+ break;
+
+ default:
+ /*
+ * If we get here, everything is out of sync, exit with error
+ */
+ return_ACPI_STATUS (AE_AML_INVALID_RESOURCE_TYPE);
+
+ } /* switch (linked_list->Id) */
+
+ /*
+ * Update the total
+ */
+ byte_stream_size_needed += segment_size;
+
+ /*
+ * Point to the next object
+ */
+ linked_list = ACPI_PTR_ADD (struct acpi_resource,
+ linked_list, linked_list->length);
+ }
+
+ /*
+ * This is the data the caller needs
+ */
+ *size_needed = byte_stream_size_needed;
+ return_ACPI_STATUS (AE_OK);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_rs_get_list_length
+ *
+ * PARAMETERS: byte_stream_buffer - Pointer to the resource byte stream
+ * byte_stream_buffer_length - Size of byte_stream_buffer
+ * size_needed - u32 pointer of the size buffer
+ * needed to properly return the
+ * parsed data
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Takes the resource byte stream and parses it once, calculating
+ * the size buffer needed to hold the linked list that conveys
+ * the resource data.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_rs_get_list_length (
+ u8 *byte_stream_buffer,
+ u32 byte_stream_buffer_length,
+ acpi_size *size_needed)
+{
+ u32 buffer_size = 0;
+ u32 bytes_parsed = 0;
+ u8 number_of_interrupts = 0;
+ u8 number_of_channels = 0;
+ u8 resource_type;
+ u32 structure_size;
+ u32 bytes_consumed;
+ u8 *buffer;
+ u8 temp8;
+ u16 temp16;
+ u8 index;
+ u8 additional_bytes;
+
+
+ ACPI_FUNCTION_TRACE ("rs_get_list_length");
+
+
+ while (bytes_parsed < byte_stream_buffer_length) {
+ /*
+ * The next byte in the stream is the resource type
+ */
+ resource_type = acpi_rs_get_resource_type (*byte_stream_buffer);
+
+ switch (resource_type) {
+ case ACPI_RDESC_TYPE_MEMORY_24:
+ /*
+ * 24-Bit Memory Resource
+ */
+ bytes_consumed = 12;
+
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_mem24);
+ break;
+
+
+ case ACPI_RDESC_TYPE_LARGE_VENDOR:
+ /*
+ * Vendor Defined Resource
+ */
+ buffer = byte_stream_buffer;
+ ++buffer;
+
+ ACPI_MOVE_16_TO_16 (&temp16, buffer);
+ bytes_consumed = temp16 + 3;
+
+ /*
+ * Ensure a 32-bit boundary for the structure
+ */
+ temp16 = (u16) ACPI_ROUND_UP_to_32_bITS (temp16);
+
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_vendor) +
+ (temp16 * sizeof (u8));
+ break;
+
+
+ case ACPI_RDESC_TYPE_MEMORY_32:
+ /*
+ * 32-Bit Memory Range Resource
+ */
+ bytes_consumed = 20;
+
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_mem32);
+ break;
+
+
+ case ACPI_RDESC_TYPE_FIXED_MEMORY_32:
+ /*
+ * 32-Bit Fixed Memory Resource
+ */
+ bytes_consumed = 12;
+
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_fixed_mem32);
+ break;
+
+
+ case ACPI_RDESC_TYPE_EXTENDED_ADDRESS_SPACE:
+ /*
+ * 64-Bit Address Resource
+ */
+ buffer = byte_stream_buffer;
+
+ ++buffer;
+ ACPI_MOVE_16_TO_16 (&temp16, buffer);
+
+ bytes_consumed = temp16 + 3;
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_address64);
+ break;
+
+
+ case ACPI_RDESC_TYPE_QWORD_ADDRESS_SPACE:
+ /*
+ * 64-Bit Address Resource
+ */
+ buffer = byte_stream_buffer;
+
+ ++buffer;
+ ACPI_MOVE_16_TO_16 (&temp16, buffer);
+
+ bytes_consumed = temp16 + 3;
+
+ /*
+ * Resource Source Index and Resource Source are optional elements.
+ * Check the length of the Bytestream. If it is greater than 43,
+ * that means that an Index exists and is followed by a null
+ * terminated string. Therefore, set the temp variable to the
+ * length minus the minimum byte stream length plus the byte for
+ * the Index to determine the size of the NULL terminated string.
+ */
+ if (43 < temp16) {
+ temp8 = (u8) (temp16 - 44);
+ }
+ else {
+ temp8 = 0;
+ }
+
+ /*
+ * Ensure a 64-bit boundary for the structure
+ */
+ temp8 = (u8) ACPI_ROUND_UP_to_64_bITS (temp8);
+
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_address64) +
+ (temp8 * sizeof (u8));
+ break;
+
+
+ case ACPI_RDESC_TYPE_DWORD_ADDRESS_SPACE:
+ /*
+ * 32-Bit Address Resource
+ */
+ buffer = byte_stream_buffer;
+
+ ++buffer;
+ ACPI_MOVE_16_TO_16 (&temp16, buffer);
+
+ bytes_consumed = temp16 + 3;
+
+ /*
+ * Resource Source Index and Resource Source are optional elements.
+ * Check the length of the Bytestream. If it is greater than 23,
+ * that means that an Index exists and is followed by a null
+ * terminated string. Therefore, set the temp variable to the
+ * length minus the minimum byte stream length plus the byte for
+ * the Index to determine the size of the NULL terminated string.
+ */
+ if (23 < temp16) {
+ temp8 = (u8) (temp16 - 24);
+ }
+ else {
+ temp8 = 0;
+ }
+
+ /*
+ * Ensure a 32-bit boundary for the structure
+ */
+ temp8 = (u8) ACPI_ROUND_UP_to_32_bITS (temp8);
+
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_address32) +
+ (temp8 * sizeof (u8));
+ break;
+
+
+ case ACPI_RDESC_TYPE_WORD_ADDRESS_SPACE:
+ /*
+ * 16-Bit Address Resource
+ */
+ buffer = byte_stream_buffer;
+
+ ++buffer;
+ ACPI_MOVE_16_TO_16 (&temp16, buffer);
+
+ bytes_consumed = temp16 + 3;
+
+ /*
+ * Resource Source Index and Resource Source are optional elements.
+ * Check the length of the Bytestream. If it is greater than 13,
+ * that means that an Index exists and is followed by a null
+ * terminated string. Therefore, set the temp variable to the
+ * length minus the minimum byte stream length plus the byte for
+ * the Index to determine the size of the NULL terminated string.
+ */
+ if (13 < temp16) {
+ temp8 = (u8) (temp16 - 14);
+ }
+ else {
+ temp8 = 0;
+ }
+
+ /*
+ * Ensure a 32-bit boundary for the structure
+ */
+ temp8 = (u8) ACPI_ROUND_UP_to_32_bITS (temp8);
+
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_address16) +
+ (temp8 * sizeof (u8));
+ break;
+
+
+ case ACPI_RDESC_TYPE_EXTENDED_XRUPT:
+ /*
+ * Extended IRQ
+ */
+ buffer = byte_stream_buffer;
+
+ ++buffer;
+ ACPI_MOVE_16_TO_16 (&temp16, buffer);
+
+ bytes_consumed = temp16 + 3;
+
+ /*
+ * Point past the length field and the Interrupt vector flags to
+ * save off the Interrupt table length to the Temp8 variable.
+ */
+ buffer += 3;
+ temp8 = *buffer;
+
+ /*
+ * To compensate for multiple interrupt numbers, add 4 bytes for
+ * each additional interrupts greater than 1
+ */
+ additional_bytes = (u8) ((temp8 - 1) * 4);
+
+ /*
+ * Resource Source Index and Resource Source are optional elements.
+ * Check the length of the Bytestream. If it is greater than 9,
+ * that means that an Index exists and is followed by a null
+ * terminated string. Therefore, set the temp variable to the
+ * length minus the minimum byte stream length plus the byte for
+ * the Index to determine the size of the NULL terminated string.
+ */
+ if (9 + additional_bytes < temp16) {
+ temp8 = (u8) (temp16 - (9 + additional_bytes));
+ }
+ else {
+ temp8 = 0;
+ }
+
+ /*
+ * Ensure a 32-bit boundary for the structure
+ */
+ temp8 = (u8) ACPI_ROUND_UP_to_32_bITS (temp8);
+
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_ext_irq) +
+ (additional_bytes * sizeof (u8)) +
+ (temp8 * sizeof (u8));
+ break;
+
+
+ case ACPI_RDESC_TYPE_IRQ_FORMAT:
+ /*
+ * IRQ Resource.
+ * Determine if it there are two or three trailing bytes
+ */
+ buffer = byte_stream_buffer;
+ temp8 = *buffer;
+
+ if(temp8 & 0x01) {
+ bytes_consumed = 4;
+ }
+ else {
+ bytes_consumed = 3;
+ }
+
+ /* Point past the descriptor */
+
+ ++buffer;
+
+ /*
+ * Look at the number of bits set
+ */
+ ACPI_MOVE_16_TO_16 (&temp16, buffer);
+
+ for (index = 0; index < 16; index++) {
+ if (temp16 & 0x1) {
+ ++number_of_interrupts;
+ }
+
+ temp16 >>= 1;
+ }
+
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_io) +
+ (number_of_interrupts * sizeof (u32));
+ break;
+
+
+ case ACPI_RDESC_TYPE_DMA_FORMAT:
+ /*
+ * DMA Resource
+ */
+ buffer = byte_stream_buffer;
+ bytes_consumed = 3;
+
+ /* Point past the descriptor */
+
+ ++buffer;
+
+ /*
+ * Look at the number of bits set
+ */
+ temp8 = *buffer;
+
+ for(index = 0; index < 8; index++) {
+ if(temp8 & 0x1) {
+ ++number_of_channels;
+ }
+
+ temp8 >>= 1;
+ }
+
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_dma) +
+ (number_of_channels * sizeof (u32));
+ break;
+
+
+ case ACPI_RDESC_TYPE_START_DEPENDENT:
+ /*
+ * Start Dependent Functions Resource
+ * Determine if it there are two or three trailing bytes
+ */
+ buffer = byte_stream_buffer;
+ temp8 = *buffer;
+
+ if(temp8 & 0x01) {
+ bytes_consumed = 2;
+ }
+ else {
+ bytes_consumed = 1;
+ }
+
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_start_dpf);
+ break;
+
+
+ case ACPI_RDESC_TYPE_END_DEPENDENT:
+ /*
+ * End Dependent Functions Resource
+ */
+ bytes_consumed = 1;
+ structure_size = ACPI_RESOURCE_LENGTH;
+ break;
+
+
+ case ACPI_RDESC_TYPE_IO_PORT:
+ /*
+ * IO Port Resource
+ */
+ bytes_consumed = 8;
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_io);
+ break;
+
+
+ case ACPI_RDESC_TYPE_FIXED_IO_PORT:
+ /*
+ * Fixed IO Port Resource
+ */
+ bytes_consumed = 4;
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_fixed_io);
+ break;
+
+
+ case ACPI_RDESC_TYPE_SMALL_VENDOR:
+ /*
+ * Vendor Specific Resource
+ */
+ buffer = byte_stream_buffer;
+
+ temp8 = *buffer;
+ temp8 = (u8) (temp8 & 0x7);
+ bytes_consumed = temp8 + 1;
+
+ /*
+ * Ensure a 32-bit boundary for the structure
+ */
+ temp8 = (u8) ACPI_ROUND_UP_to_32_bITS (temp8);
+ structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_vendor) +
+ (temp8 * sizeof (u8));
+ break;
+
+
+ case ACPI_RDESC_TYPE_END_TAG:
+ /*
+ * End Tag
+ */
+ bytes_consumed = 2;
+ structure_size = ACPI_RESOURCE_LENGTH;
+ byte_stream_buffer_length = bytes_parsed;
+ break;
+
+
+ default:
+ /*
+ * If we get here, everything is out of sync,
+ * exit with an error
+ */
+ return_ACPI_STATUS (AE_AML_INVALID_RESOURCE_TYPE);
+ }
+
+ /*
+ * Update the return value and counter
+ */
+ buffer_size += (u32) ACPI_ALIGN_RESOURCE_SIZE (structure_size);
+ bytes_parsed += bytes_consumed;
+
+ /*
+ * Set the byte stream to point to the next resource
+ */
+ byte_stream_buffer += bytes_consumed;
+ }
+
+ /*
+ * This is the data the caller needs
+ */
+ *size_needed = buffer_size;
+ return_ACPI_STATUS (AE_OK);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_rs_get_pci_routing_table_length
+ *
+ * PARAMETERS: package_object - Pointer to the package object
+ * buffer_size_needed - u32 pointer of the size buffer
+ * needed to properly return the
+ * parsed data
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Given a package representing a PCI routing table, this
+ * calculates the size of the corresponding linked list of
+ * descriptions.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_rs_get_pci_routing_table_length (
+ union acpi_operand_object *package_object,
+ acpi_size *buffer_size_needed)
+{
+ u32 number_of_elements;
+ acpi_size temp_size_needed = 0;
+ union acpi_operand_object **top_object_list;
+ u32 index;
+ union acpi_operand_object *package_element;
+ union acpi_operand_object **sub_object_list;
+ u8 name_found;
+ u32 table_index;
+
+
+ ACPI_FUNCTION_TRACE ("rs_get_pci_routing_table_length");
+
+
+ number_of_elements = package_object->package.count;
+
+ /*
+ * Calculate the size of the return buffer.
+ * The base size is the number of elements * the sizes of the
+ * structures. Additional space for the strings is added below.
+ * The minus one is to subtract the size of the u8 Source[1]
+ * member because it is added below.
+ *
+ * But each PRT_ENTRY structure has a pointer to a string and
+ * the size of that string must be found.
+ */
+ top_object_list = package_object->package.elements;
+
+ for (index = 0; index < number_of_elements; index++) {
+ /*
+ * Dereference the sub-package
+ */
+ package_element = *top_object_list;
+
+ /*
+ * The sub_object_list will now point to an array of the
+ * four IRQ elements: Address, Pin, Source and source_index
+ */
+ sub_object_list = package_element->package.elements;
+
+ /*
+ * Scan the irq_table_elements for the Source Name String
+ */
+ name_found = FALSE;
+
+ for (table_index = 0; table_index < 4 && !name_found; table_index++) {
+ if ((ACPI_TYPE_STRING == ACPI_GET_OBJECT_TYPE (*sub_object_list)) ||
+ ((ACPI_TYPE_LOCAL_REFERENCE == ACPI_GET_OBJECT_TYPE (*sub_object_list)) &&
+ ((*sub_object_list)->reference.opcode == AML_INT_NAMEPATH_OP))) {
+ name_found = TRUE;
+ }
+ else {
+ /*
+ * Look at the next element
+ */
+ sub_object_list++;
+ }
+ }
+
+ temp_size_needed += (sizeof (struct acpi_pci_routing_table) - 4);
+
+ /*
+ * Was a String type found?
+ */
+ if (name_found) {
+ if (ACPI_GET_OBJECT_TYPE (*sub_object_list) == ACPI_TYPE_STRING) {
+ /*
+ * The length String.Length field does not include the
+ * terminating NULL, add 1
+ */
+ temp_size_needed += ((acpi_size) (*sub_object_list)->string.length + 1);
+ }
+ else {
+ temp_size_needed += acpi_ns_get_pathname_length (
+ (*sub_object_list)->reference.node);
+ }
+ }
+ else {
+ /*
+ * If no name was found, then this is a NULL, which is
+ * translated as a u32 zero.
+ */
+ temp_size_needed += sizeof (u32);
+ }
+
+ /* Round up the size since each element must be aligned */
+
+ temp_size_needed = ACPI_ROUND_UP_to_64_bITS (temp_size_needed);
+
+ /*
+ * Point to the next union acpi_operand_object
+ */
+ top_object_list++;
+ }
+
+ /*
+ * Adding an extra element to the end of the list, essentially a NULL terminator
+ */
+ *buffer_size_needed = temp_size_needed + sizeof (struct acpi_pci_routing_table);
+ return_ACPI_STATUS (AE_OK);
+}